§ 209-t. Contracts for joint fire alarm systems. The local governing bodies of the several villages and fire districts of the state are hereby authorized on behalf of their respective villages and fire districts to enter into contracts with any other village or fire district for the construction, operation and maintenance and joint use of a fire alarm system at their joint expense (each village or fire district bearing a part of the expense in proportion to the assessed valuation of real estate in such village or fire district, or on such other basis or division as may be jointly agreed upon).